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1.
Fusarium oxysporum f. sp. lycopersici and Rhizoctonal solani were grown in a complete 1.0 mM nutrient solution, and in solutions where Ca, Fe, K, Mg, N, P, and S were either excluded (0.0 mM) or included at depleted levels (0.1 mM) while all other constituents were maintained at 1.0 mM levels. Dry weight of both fungi were determined. For both fungi some of the lowest dry weights were recorded for samples grown in the complete solution. Exclusion of K, Mg, and S significantly increased dry weight of Fusarium. Inclusion at the 0.1 mM level of most components significantly increased Fusarium dry weight over values for both the complete and corresponding excluded nutrient solutions. The exception was S where there was no difference between excluded and 0.1 mM solutions. For Rhizoctonia dry weights in Fe excluded solutions were less than the complete solution, while dry weights in S excluded solutions were greater than the complete solution. At the 1.0 mM level Fe, K, and Mg dry weights were significantly increased over the dry weights produced in both the complete and deficient solutions.  相似文献   
2.
Mangoes (Mangifera indica) are grown in many warm regions of the world; for example, in Australia, Brazil, India, South America, and the United States (California and Florida), and along the shores of the Mediterranean sea (Egypt, Italy, and Spain). In Egypt, many varieties yielding delicious fruits are grown in large quantities (50,000 tons annually). Mango kernels are used for feeding mammals and chickens. Starch has been isolated from mango and its physical properties studied.The aim of the present work was to study the polysaccharides present in mango kernels.  相似文献   
3.
A sulphated heteropolysaccharide (~15% of the acid-extractable material) isolated from the brown alga Dictyota dichotoma contains residues of D-glucuronic acid, D-galactose, D-mannose, D-xylose, and L-fucose1. Partial hydrolysis of the polysaccharide with acid gave one neutral and two acidic oligosaccharides. The behaviour towards periodate of the polysaccharide before and after partial hydrolysis, alkali-treatment, and methanolysis has been studied. Evidence is thereby provided that the polysaccharide is partially sulphated and composed of (1→4)-linked residues of D-glucuronic acid, D-galactose, D-mannose, and D-xylose, and (1→2)-linked L-fucose.  相似文献   
4.
Summary The growth rates of immobilized Penicillium chrysogenum strains are important in their application to semicontinuous penicillin production. Immobilized P. chrysogenum strains produced about 10–15% less biomass but about 1–2 times more penicillin than free suspended mycelia.In a chemically defined medium an industrial P. chrysogenum strain, S1, produced about 10–12 times more penicillin than strain ATCC 12690. In a complex medium the immobilized P. chrysogenum S1 produced about 12% penicillin more than in shaken cultures. In bubble column fermentations, penicillin production was 163% higher in the complex medium than in the chemically defined medium.  相似文献   
5.
Some properties of the crude lyophilized fibrinolytic enzyme produced by Cochliobolus lunatus in surface culture were studied. Enzyme concentrations over the range from 0.16 to 10.16 mg/mL showed that concentration above a certain level ceased to be the limiting factor controlling enzyme action. At pH 6.8 and a temperature of 40°C, the fibrinolytic enzyme showed maximal activity at a human fibrin concentration of 2 mg/mL. The optimum pH values for enzyme activity were 6.98 and 7.0, using Sørensen and Mcllvaine buffers, respectively. Fibrinolytic enzymes were isolated from a static culture of Cochliobolus lunatus; isolation was carried out with various agents. Ammonium sulphate yielded the highest recovered fibrinolytic activity. The fraction salted out by precipitation at 25% ammonium sulphate saturation possessed the highest recovered fibrinolytic activity compared to the ammonium sulphate, ethanol, and acetone fractions.  相似文献   
6.
The ultrastructure of a lateral organ in the head of Polyxenus lagurus which has been recently erroneously termed cerebral gland is described. It turned out to be a neurohaemal organ and not a gland, apparently homologous to the organ of Gabe of the luliformia.  相似文献   
7.
Moxifloxacin and ofloxacin are two broad-spectrum quinolone antibiotics. They are among the most widely used antibiotics, at this time, applied to control the COVID-19 pandemic. Hydroxychloroquine is an FDA-approved drug for the treatment of COVID-19. This work describes a simple, green, selective, and sensitive spectrofluorimetric method for the assay of moxifloxacin and ofloxacin in the presence of hydroxychloroquine, two co-administered mixtures used in the treatment of hospital-acquired pneumonia in patients with COVID-19. Simultaneous assay of hydroxychloroquine and moxifloxacin was carried out in methanol using a direct spectrofluorimetric method (method I) at 375 and 550 nm, respectively, after excitation at 300 nm. The direct spectrofluorimetric assay was rectilinear over concentration ranges 50.0–400.0 and 300.0–2500.0 ng/ml for hydroxychloroquine and moxifloxacin, respectively, with limits of detection (LOD) of 6.4 and 33.64 ng/ml and limits of quantitation (LOQ) of 19.4 and 102.6 ng/ml, respectively, for the two drugs. The assay for hydroxychloroquine and ofloxacin was carried out by measuring the first derivative synchronous amplitude for hydroxychloroquine at the zero crossing point of ofloxacin and vice versa at Δλ = 140 nm (method II). Hydroxychloroquine was measured at 266 nm, while ofloxacin was measured at 340 nm over the concentration range 4–40 ng/ml for hydroxychloroquine and 200–2000 ng/ml for ofloxacin with LOD of 0.467 and 25.3 ng/ml and LOQ of 1.42 and 76.6 ng/ml, respectively, for the two drugs. The two methods were validated following International Conference on Harmonization guidelines and were applied to the analysis of the two drugs in plasma with good percentage recoveries (109.73–93.17%).  相似文献   
8.
Thirteen thermohilic genera and 19 species in addition to one variety of each of M. pulchella and H.grisea were collected from wheat and broad-bean straw composts at 45 °C. In wheat and broad-bean, all thermophilic fungi were completely checked between 4–9 days, and 1–8 days composting when the temperature ranged between 58 ° and 67 °C, and 58 ° and 70 °C respectively, and reappeared, represented by P. duponti, M. albomyces, T. lanuginosus and S. thermophile, after 9 or 10 days composting when the temperature decreased to 51.5 °–54 °C. Wheat and broad-bean straw composts were analyzed biochemically to follow the changes in ethanol and diastase soluble, hemicellulose, cellulose and lignin fractions during composting.  相似文献   
9.
Using a rotating disk with a slit of variable width, a continuous wave argon ion laser, and an Optical Multichannel Analyzer for detection, a new technique is reported which should, in principle, be capable of recording resonance Raman spectra with time resolution of 100 ns. The resonance Raman spectra of the intermediates of the photosynthetic cycle of bacteriorhodopsin are recorded on the microsecond time scale. Both the kinetic results and the resonance enhancement profile suggest that deprotonation results in an intermediate preceding bM412 that has an optical absorption maximum at a wavelength longer than that of bM412.  相似文献   
10.
Ninety-five species and seven varieties which belong to thirty-nine genera were isolated from 74 soil samples from salt marshes. At 28°C, on 30% sucrose Czapek's agar, ninety species and four varieties which belong to thirty-six genera were encountered, from which A. niger, A. fumigatus A. terreus and P. notatum were the most frequent. On 60% sucrose Czapek's agar, sixty-three species and three varieties were recovered which belong to twenty-five genera, from which A. niger, A. fumigatus, Cladosporium herbarum and A. terreus were the most frequent.At 45°C, on 30% sucrose, sixteen species and four varieties were identified, but on 60% sucrose, fourteen species and three varieties were isolated. A. fumigatus and A. niger were the most frequent on both sucrose concentrations.The results reveal that the soil samples poor in total osmophilic fungi (at 28°C) were significantly higher in their content of total soluble salts, Na and K and significantly lower in the average number of species per soil samples than the rich ones; the difference was nonsignificant in case of organic matter.  相似文献   
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